FitSmart Fat Burner UK Reviews FitSmart Fat Burner helps you burn fat as well as improve your metabolism at the same time. One may also feel energized and uplifted after taking FitSmart Fat Burner pills. The FitSmart Fat Burner product, a combination of various natural ingredients including niacin (vitamin B3), raspberry fruit extract, green tea leaf extract, guarana seed extract and N-acetyl-L-carnitine, offers a versatile range of potential weight management benefits.